Yellow to brown dye.



a yellow etc.

' To all whommay concern:- i

UNITED srarss AUGUST- BLANK Ann WLADIMIR aomonow;

FFICE.

OF LEVERKUSEN, NEAR COLOGNE,

GERMANY, ASSIGNORS TO FARBENFABBIKEN VQRM FRIEDR. BAYER & CO OF ELBERFELD, GERMANY, A CORBQRATION OE GERMANY.

' YELLOW 'ro' BROWN DYE.

No Drawing.

Be it known that we, A Gos'r BLANK and WLADIMIR RODIONQW, chemists, citizens of, respectively, Germany ing is aspecification.

We have "found thatnew and valuable dyestuffs are, obtained by" treating with aromatic aminoazo compounds the known dyestuffs which can be obtained by treating para-nitro toluenesulfonic acid with caustic sodalye. Thesedyestutts are known in com merce as, cut-cumin S, direct yellow,- sun They are chemically az0xystilbene disulfonic acid or azoazoxydistilbene disulfonjicjacid. (Green, Journal of Chem-- z'cal Society 89 p; 1610).

The new dyestuffs thus obtained are after being dried and pulverizedbrown to black powders soluble in water with'from a yellow to brown color and dyeing unmord'anted cotton from yellow to orange to brown shades which ar.e distinguished by thcir'excellent fastness tolight and their fastness to oxidizing agents.

Example: Direct yellow (azoazoxydistilbene sulfonic acid) obtained from 70 parts by weight of para-nitro-toulene sulfonic acid (sodium salt) stirred up with water and 26 parts of aminoazobenzene sulfonate of sodium 50 partsof 30 'per cent. caustic soda lye and 1,000 parts of water are added.

The resulting mixture is then heated to boiling for 20 hours in a vessel provided with a reflux condenser and astirr'er. The

solution is neutralized with mineral -acid and the dyestuflis precipitated with salt. It is after being dried and pulverized 'a yellowish-brown powder which is soluble in waterv with an orange color, and which is soluble in concentrated sulfuric ac d with a violet-black color being precipitated in the shape of brown flakes by the addition of water. It dyes nnmordanted cotton orange shades.

Instead of direct yellow other of the above mentioned dyes or other aminoazo com Specification of Letters Patent. Application file d- October 14, 1909. Serial No. 522,616.

and Russia, residing at Leverkusen, near Cologne, Germany, have invented new" and useful-Improvements in New Coloring-Matter, of which'the follow- "pounds may be used 6. g. amin'oazotolu'en esulfomc acid, metaor para- 'su1fan1l1c acidazoelniaphthylannn, vparafchloroanilm sultonic. acid-azo-l-naphthylamin, anthranilic acid-azo-l-naphthylamin, metaor paraami nobenzoic acid-azo-l-naphthylamin, benzene azo l naphthylamin-(isulfonic acid, aminobenzene azo 2 phenylamino 8 naphthol=6'-sulfonic acid, aminobenzene azo 2 phenylamino-fi-naphthol-T-sulfonic acid, 1- naphthylamin azo l naphthylamin 6 sulfonic acid, l-n'aphthylamin-fi-sulfonic acidgazo-l-naphthylamin, 2-naphthyla'min L8-di alkaline solution).

dyestuffs are after being dried and pu1verized brown to blaclcpowders soluble in wa-v ter with a yellow to brown color; and dycing unlnordanted cotton from yellow to orange to brown shades fast to light and to the action of oxidizing agents, substantially as described.

12. The herein described new dyestulf obtainable by condensing direct yellow with amin oazobenzene-sulfonic acid, which dyestutf is alterbeing dried and pulverizeda yellowish-brown powder, which is soluble in water with an orange color, soluble in concentrated sulfuric acid with a violetblack color, of brown flakes from such a solution by addition of water; and dyeing unmor danted cotton orange shades, substantially as described.

v In testimony whereof we have hereunto set our hands in the presence ottWo subscribing witnesses.

' AUGUST- BLANK. '[L.s.] W'LADIMIR RQDIONOlV- [L- s.]

lVitn'esses O'r'ro KoNIo,

Crras. J. WRIGHT.

being precipitated in the shape Patented Mar. 1,1910.

sulfonic' acid-azmLnaphthylamin', l-naph-- I thylaminazo-2-amino-.8-naphthol-6-sulfonic' sulfonicacid with eaustic soda lye, Which 

